I see that this is your first post, so let me be the first to welcome you to USA Carry.
As for your question, I can't imagine any state (perhaps with the exception of Ohio) that doesn't allow permit holders to carry however they want while in a vehicle.
I noticed in your post that no mention was made of what state you're referring to. We'd have and easier time answering your question if we knew what state you were in.
Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
Benjamin Franklin